Furnace Pilot Light Won't Stay Lit in Irving, TX

A furnace pilot light that won't stay lit is a specific complaint, and in Irving it often gets used for two different furnaces. One still has a small standing flame that you light by hand. The other has not had a standing pilot in years. It clicks or glows, the burners may catch, and then the gas shuts off. Those are not the same repair.

If you smell gas (a rotten egg odor), stop here. Do not relight anything, flip switches, or use a phone inside. Leave the home and call your gas utility or 911 from outside. If a carbon monoxide alarm sounds, or anyone has a headache, nausea, or dizziness that eases outdoors, get everyone out and call 911. Carbon monoxide has no smell. A pilot that went out is not a test for it.

Do not bypass the safety that holds the gas valve. A thermocouple exists so the gas shuts off when the flame is gone. Jumpering it, tying the knob down, or holding the valve open is how unburned gas gets into the furnace. Leave that part to a technician.

Smoke, a hot-plastic smell, or a breaker that trips means the furnace stays off. Reset a breaker once. A second trip stays off. Do not open the electrical compartment or the burner cover.

Which furnace you actually have

Standing pilot. A small flame burns all the time, or it is supposed to. You light it with the instructions on the door, hold a knob, and the flame should stay when you let go. This is more common on older Irving furnaces. Newer equipment usually does not have one.

Hot surface igniter or spark. No standing flame. On a call for heat the draft motor starts, an igniter glows or sparks, the burners light, and a flame sensor has to prove the flame. If you never see a small flame while the furnace is idle, you do not have a pilot-light problem. The sequence, and the safe checks, are in furnace not igniting. A furnace that never starts at all is the furnace not kicking on checklist.

Intermittent pilot. A spark lights a pilot only when there is a call for heat, then the main burners open. It can look like a standing pilot if you catch it mid-cycle. It is still not a flame you should be relighting by hand.

If the only clue is a smell when the furnace starts, that is a different visit. Weird smell when the furnace turns on in Irving sorts those odors. A gas smell is not one of the smells you wait out.

If it is a standing pilot that dies when you let go

The gas valve on these furnaces stays open only while a thermocouple or thermopile is hot from the pilot flame. When you release the knob and the flame dies, that sensor is usually not staying hot enough. A dirty pilot opening, a flame that is lifting off the sensor, a draft across the burner, or low gas pressure can cause the same symptom. The fix is to find which one, not to defeat the sensor.

What you can do once, if you do not smell gas:

• Read the lighting label on the furnace door and follow it one time. If there is no label, do not improvise a procedure.
• If the pilot lights and goes out when you release the knob, stop. Do not try a second long hold, and do not take the burner assembly apart.
• Look at other gas appliances from a safe distance. If the stove will not light either, call the gas utility. Do not open a gas pipe.
• Set the thermostat to Heat and the fan to AUTO only after the pilot is staying lit on its own. A thermostat problem will not make a standing pilot die in your hand.

What you should not do: adjust the pilot screw, sand a thermocouple in place and call it repaired, bypass the sensor, or keep clicking a lighter into a burner compartment that may already have gas in it. Those are not homeowner checks. Furnace repair is the visit that tests the thermocouple, the draft, and the valve without holding the gas open by force.

A yellow, lazy pilot, soot, or a flame that blows around can mean a vent problem or a burner that is not getting air the way it should. Leave the furnace off. Do not "fix" that by opening the flue.

Safe checks that are not a relight

These apply whether the furnace is a standing pilot or an electronic ignition, and none of them require the burner cover to come off.

• Filter. If you cannot see light through it, replace it with the size on the frame. A packed filter overheats a furnace that does manage to light. Do not run it with no filter. Seat the blower door so the safety switch can close.
• Power. A switch on the cabinet, or a breaker, can be off. Reset a tripped breaker once.
• Vents. Open supplies and uncover returns. This will not relight a pilot. It keeps a furnace that does light from tripping a limit switch.
• Repeat resets. Turn the power off for about 30 seconds and back on once. If it locks out again, stop. Relighting over and over is how a small gas smell becomes a large one.

Repair, and when to leave it off

A thermocouple, a thermopile, a cleaned pilot orifice, or a draft that was blowing the flame off the sensor is a repair on a furnace whose heat exchanger and flue are sound. You should hear what failed and the price before parts go in. The name on the cabinet does not tell you which of those it is.

Leave the furnace off, and do not shop for a replacement from inside a house that smells like gas, if you see soot, a strong exhaust odor, scorch marks, or a rusted flue. A cracked heat exchanger is not a pilot part. Age alone is not the verdict either. An older Irving furnace with a standing pilot can still be worth repairing when the exchanger is sound. A younger furnace with a damaged exchanger is not.

HVAC service in Irving is the local page if you want that furnace looked at before the next cold night.

Getting the pilot sorted out

Boost Air And Plumbing repairs gas furnaces in Irving, Arlington, Grand Prairie, Fort Worth, and nearby communities. We do not install boilers. See our furnace repair service and HVAC service in Irving. Call (817) 612-9107 or book online. Hours are Monday through Saturday, 8am to 7pm, with after-hours and Sunday emergency appointments available.

Frequently asked questions

Why won't my furnace pilot light stay lit? On a furnace that still has a standing pilot, the usual reason is that the thermocouple or thermopile is not staying hot enough to hold the gas valve open. A dirty pilot opening, a draft, or a weak gas supply can do the same thing. The gas shutting off is the safety working. Do not bypass that part. If you smell gas, leave the home and call the gas utility or 911 from outside.

Does my Irving furnace even have a pilot light? Many furnaces from the last couple of decades do not. They light with a hot surface igniter or a spark, then a flame sensor proves the burners. A small standing flame you can see with the burners off is a pilot. A glow and a click, with no standing flame, is a different problem. Do not take the burner cover off to hunt for a flame.

Can I relight the pilot myself? Only if you do not smell gas and the furnace door has lighting instructions. Follow that label once. If the pilot will not stay lit when you release the knob, stop. Do not hold the gas valve open, do not bypass the thermocouple, and do not use a lighter if you smell gas. Repeated attempts can fill the burner area with unburned gas.

Is a pilot that keeps going out dangerous? The valve is supposed to close when the pilot is out, so a furnace that simply will not stay lit is often the safety doing its job. It is dangerous if you smell gas, if you bypass the thermocouple to force it, or if anyone feels sick. A gas smell means leave and call the gas utility or 911 from outside. A carbon monoxide alarm, or headache, nausea, or dizziness that eases outdoors, means get everyone out and call 911.

Is this a repair or a new furnace? A thermocouple, a cleaned pilot, or a draft problem on a furnace with a sound heat exchanger is usually a repair. Soot, a yellow lazy flame, a rusted cabinet, or a cracked heat exchanger means leave the furnace off. Age alone is not the verdict. You should hear what failed, and the price, before parts are replaced.